JP5463672B2 - Double shutoff oil supply valve - Google Patents

Description

(Related application to be referenced)
This application claims the benefit of Patent Document 1 filed on February 13, 2006 and Patent Document 2 filed on October 12, 2006, the disclosures of which are incorporated herein by reference.
US Provisional Patent Application No. 60/777222 Specification US Provisional Patent Application No. 60/85159

  The present invention relates to a shut-off valve for a vehicle fuel system, and more particularly to a valve designed to shut off two or more evaporative gas passages in the fuel system.

  The vehicle fuel system includes a mechanism that detects when the fuel in the tank has reached a full tank level. This mechanism then shuts off the refueling nozzle to prevent additional fuel from entering the tank and keeps the pressure in the tank below a desired level. Part of this mechanism includes a recirculation line that is connected via a T connection to the vent line between the fuel tank and the evaporative gas storage canister or directly to the fuel tank. This recirculation line (also known as a “dip tube”), when connected to a fuel tank, is interrupted by a liquid or liquid sensing valve when the fuel tank is full. The fuel system generally uses a canister that adsorbs fuel evaporative gas and prevents it from being released to the atmosphere. The evaporative gas flows through the tubes that form the canister line, which should also be shut off when the fuel is at a full tank level. Ideally, the recirculation line and the canister line are shut off at the same time when the fuel tank reaches a full tank level to prevent liquid fuel from flowing between these lines, Do not enter the line.

  In order to protect both the recirculation line and the canister line from liquid inflow, the present invention provides a double shutoff refueling valve that responds to the full tank level of the fuel tank by simultaneously closing the recirculation line and the canister line. For the most part.

  The valve of the present invention includes at least one float having one or more sealing surfaces corresponding to each of the recirculation line and the canister line. This sealing surface is arranged at the top of the float of the float valve. When the fuel in the fuel tank reaches a full tank level, the float moves upward and closes the recirculation line and the canister line simultaneously.

  In one embodiment of the invention, the valve has a coaxial seal in which the two valve openings corresponding to the dip tube and the evaporative gas passage are arranged concentrically. In other embodiments, these sealing surfaces can be, for example, two separate sealing surfaces, or any other sealing shape corresponding to the arrangement of dip tubes and evaporative gas vent passages in the fuel tank. can do.

FIG. 1 is a representative schematic of a fuel system 100 that includes a fuel limited vent valve (FLVV) 102 of the present invention, which operates as a double shutoff refueling valve. The system 100 includes a fuel line 104 having a seal 106 designed to seal around a fuel tank 103 and a fuel nozzle (not shown). The recirculation line 108 connects the fuel tank 103 to the refueling pipe 104 and recirculates the fuel evaporative gas from the fuel tank 103 to the refueling pipe 104, whereas the canister line 110 allows the fuel tank 103 to pass the excess fuel. Connected to a canister (not shown) for storing evaporative gas. The ends of recirculation line 108 and canister line 110 open into tank 103, and FLVV 102 is provided to close both lines simultaneously to prevent liquid fuel from flowing from one line to the other. It has been. By closing the FLVV 102, the negative pressure in the recirculation line 108 increases, and the fuel supply nozzle is shut off. As a result, the pressure of the fuel evaporative gas in the fuel tank 103 increases, and this pressure is increased when a mechanical seal leaks or when a conventional fuel system that does not have a mechanical seal structure is used. It becomes the pressure which blows off the intercepted fuel. The system 100 may include a vent valve 112 that connects to the canister line 110, but the valve 112 is not part of the present invention.

  FIGS. 1-5 illustrate the structure of the system 100 in which the recirculation line 108 and the canister line 110 are concentrically arranged. Although these figures show that the canister line 110 is located outside the recirculation line 108, the recirculation line 108 is located outside the canister line 110 without departing from the scope of the present invention. The FLVV 102 may close these lines 108, 110. Also, without departing from the scope of the present invention, the recirculation line 108 and the canister line 110 are placed next to each other (eg, as shown in FIG. 6) so that the FLVV 102 closes these lines. Note that you may.

  2-4 illustrate a FLVV 102 according to one embodiment of the present invention. In this embodiment, the FLVV 102 has a coaxial seal structure. The FLVV 102 includes a cylindrical housing 120 surrounding the float 122, and the float 122 is biased by an elastic member 124 (for example, a spring). The lid 126 acts as a closing member at the top of the housing 120. In one embodiment, the housing 120 has a plurality of slots 128 that engage a plurality of tabs 130 formed around the lid 126. Other methods may be used to attach the lid to the housing.

  In this embodiment, the lid 126 has one or more first openings 132 surrounding the periphery of the tube 134 having the second openings 136, forming a coaxial structure. The first opening 132 is formed in a first tube (ring) 138 protruding from the upper flat surface of the lid 126. The first tube 138 includes a first groove 140 that holds a first seal 142 such as an O-ring seal. The tube 134 extends beyond the first ring 138 and has a second seal 144, such as an O-ring seal, that surrounds the second opening 136. A lip 146 may be formed on the tube 134 to support the second seal 144. The inside of the FLVV 102 of the present embodiment can have any known float valve structure.

As shown in FIG. 2, the coaxial structure of the first seal 142 and the second seal 144 corresponds to the concentric structure of the recirculation line 108 and the canister line 110. In this embodiment, the end of recirculation line 108 is higher than the end of canister line 110. Above the FLVV 102, the tube 134 extends into the recirculation line 108 and a second seal 144 abuts and seals against the inner wall of the recirculation line 108. The end of the recirculation line 108 may be supported against the lip 146 when the FLVV 102 is properly positioned. The first seal 142 contacts and seals the inner wall of the canister line 110 and concentrically surrounds the recirculation line 108. The end of the canister line 110 may be supported in contact with the top surface of the lid 126 when the FLVV 102 is properly positioned.

When the fuel level in the fuel tank 103 is lower than the full tank level, the float 122 remains at the bottom of the housing 120 and the recirculation line 108 and the canister line 110 remain open. Therefore, the fuel evaporation gas, between the recirculation line 108 and the canister line 110 and fuel tank 103 can be freely distributed through the side opening 146 of the housing 120. When the fuel level in the fuel tank 103 reaches a full tank level, the liquid fuel flows into the housing 120 through the side opening 146 and raises the float 122 to cause the first and second openings of the lid 126 to be opened. 132, 136 are closed, thereby closing the recirculation line 108 and the canister line 110 simultaneously. This double shut-off function allows both lines 108, 110 to be shut off quickly and simultaneously, minimizing tank pressure rise and liquid fuel flowing between these lines.

  FIG. 5 shows an FLVV 102 according to another embodiment of the present invention. In this embodiment, the float 122 has a ribbon valve 150 attached to its upper surface. The ribbon valve 150 utilizes the flexibility of the ribbon to seal both openings 132, 134 simultaneously without requiring additional parts or shapes to accommodate two separate sealing surfaces. In the preferred embodiment, the sealing surface associated with the (outer) first opening 132 is in the (central) second opening 134 because the ribbon is flexible and the sealing surface is rigidly secured. It is slightly longer (ie, closer to the ribbon / float) than the associated sealing surface. This liquid seal thus reliably prevents fuel from leaking from the fuel tank and flowing into any line.

  6 and 7 illustrate an embodiment of the present invention in which the recirculation line 108 and the canister line 110 are arranged side by side rather than concentrically. FIG. 6 has a tiltable seal mechanism 152 with two line seals that align with the recirculation line 108 and the canister line 110. This slight tilting movement of the sealing mechanism 152 compensates for slight positional variations of the lines 108, 110, allowing the float 122 to rise and close them tightly with the seal 154. FIG. 7 shows a structure having two float valves 160 each containing a float 122 inside the housing 120. The float valve 160 is provided in the tank 103 so that the float 122 closes the lines 108 and 110 simultaneously. Although FIG. 7 shows two separate housings, each holding a float, the two floats may be housed in a single housing.

  By incorporating a valve structure that simultaneously closes the recirculation line and the canister line, the fuel system of the present invention can reliably and quickly shut off the nozzle when the fuel in the tank reaches a predetermined full level. . Rapid valve closing minimizes tank pressure build-up and can prevent liquid from flowing between these lines by closing the two lines simultaneously.

1 is a representative schematic diagram illustrating a fuel system including a double shutoff fuel valve according to the present invention. FIG. 2 is a representative schematic longitudinal cross-sectional view of a double shutoff oil valve in the system of FIG. 1 according to one embodiment of the present invention. It is a perspective view of the double cutoff oil supply valve of FIG. It is the figure which fractured | ruptured FIG. 3 along the 4-4 line. It is a typical schematic longitudinal cross-sectional view of the double cutoff oil supply valve which concerns on other embodiment of this invention. It is a typical schematic longitudinal cross-sectional view of the double cutoff oil supply valve which concerns on further another embodiment of this invention. It is a typical schematic longitudinal cross-sectional view of the double cutoff oil supply valve which concerns on further another embodiment of this invention.

Claims (12)

A fuel limiting vent valve for closing a first line and a second line in a fuel system,
A housing;
A single float disposed within the housing and having a flexible sealing mechanism disposed on an upper surface;
A lid attached to the housing and having a first opening corresponding to the first line and a second opening corresponding to the second line;
The first opening and the second opening are arranged concentrically along a vertical axis,
The lid includes a first tube having the first opening extending from a flat surface of the lid, and a second tube having the second opening extending beyond the first tube,
The first opening protrudes slightly to the float side than the second opening,
The said float is provided so that the said sealing mechanism which has flexibility may close the said 1st and 2nd opening substantially simultaneously by a single valve body.   The valve according to claim 1, further comprising a first seal surrounding the periphery of the first opening and a second seal surrounding the periphery of the second opening.   The valve according to claim 1, wherein the first opening includes a plurality of openings arranged around the second opening. A first seal surrounding the first opening comprising the plurality of openings;
The valve according to claim 3, further comprising a second seal surrounding the second opening.   The valve according to claim 4, wherein the first pipe has a groove for holding the first seal, and the second pipe has a lip for supporting the second seal.   The valve according to claim 1, wherein the sealing mechanism includes a flexible ribbon seal capable of sealing both the first and second openings. A fuel tank,
A fuel supply pipe connected to the fuel tank;
A recirculation line connecting between the fuel supply pipe and the fuel tank and opening into the fuel tank by a first opening;
A canister line connected to the fuel tank to exchange fuel evaporative gas with the canister;
A fuel restriction vent valve disposed in the fuel tank;
The fuel limiting vent valve is
A housing;
A single float disposed within the housing and having a flexible sealing mechanism disposed on an upper surface;
A lid attached to the housing and having a first opening corresponding to the recirculation line and a second opening corresponding to the canister line;
The first opening and the second opening of the lid of the housing are arranged concentrically;
The first opening protrudes slightly to the float side than the second opening,
The float is provided such that when the fuel supply level in the fuel tank reaches a predetermined level, the flexible sealing mechanism closes the first and second openings almost simultaneously by a single valve body. A vehicle fuel system.   The system of claim 7, wherein the valve further comprises a first seal surrounding the first opening and a second seal surrounding the second opening.   8. The system of claim 7, wherein the first opening comprises a plurality of openings disposed around the second opening. A first seal surrounding the first opening comprising the plurality of openings;
The system according to claim 9, further comprising a second seal surrounding the second opening. The lid includes a first tube having the first opening and a second tube having the second opening;
The said 1st pipe | tube has a groove | channel which hold | maintains the said 1st seal | sticker, The said 2nd pipe | tube has a lip which supports the said 2nd seal | sticker, The Claim 10 characterized by the above-mentioned. The described system.   The system according to claim 7, further comprising a nozzle seal mechanism disposed in the oil supply pipe.

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